Processes and intermediates for making sweet taste enhancers

ABSTRACT

The present invention includes methods/processes and intermediates for preparing compounds having structural Formula (I): 
                         
wherein X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage application of InternationalApplication Number PCT/US2009/052048, filed Jul. 29, 2009, which claimsthe benefit of U.S. Provisional Application No. 61/085,206, filed Jul.31, 2008 and entitled “PROCESSES AND INTERMEDIATES FOR MAKING SWEETTASTE ENHANCERS”, and U.S. Provisional Application No. 61/167,654, filedApr. 8, 2009 and entitled “PROCESSES AND INTERMEDIATES FOR MAKING SWEETTASTE ENHANCERS”. The disclosures of these aforementioned applicationsare herein incorporated by reference in their entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates to intermediates and processes/methods forpreparing compounds having structural formula (I) or their salts, asdescribed below.

BACKGROUND OF THE INVENTION

Obesity, diabetes, and cardiovascular disease are health concerns on therise globally, but are growing at alarming rates in the United States.Sugar and calories are key components that can be limited to render apositive nutritional effect on health. High-intensity sweeteners canprovide the sweetness of sugar, with various taste qualities. Becausethey are many times sweeter than sugar, much less of the sweetener isrequired to replace the sugar.

High-intensity sweeteners have a wide range of chemically distinctstructures and hence possess varying properties, such as, withoutlimitation, odor, flavor, mouthfeel, and aftertaste. These properties,particularly flavor and aftertaste, are well known to vary over the timeof tasting, such that each temporal profile is sweetener-specific(Tunaley, A., “Perceptual Characteristics of Sweeteners”, Progress inSweeteners, T. H. Grenby, Ed. Elsevier Applied Science, 1989)).

Sweeteners such as saccharin and6-methyl-1,2,3-oxathiazin-4(3H)-one-2,2-dioxide potassium salt(acesulfame potassium) are commonly characterized as having bitterand/or metallic aftertastes. Products prepared with 2,4-dihydroxybenzoicacid are claimed to display reduced undesirable aftertastes associatedwith sweeteners, and do so at concentrations below those concentrationsat which their own tastes are perceptible. In contrast, somehigh-intensity sweeteners, notably sucralose(1,6-dichloro-1,6-dideoxy-β-D-fructofuranosyl-4-chloro-4-d-eoxy-α-D-galacto-pyranoside)and aspartame (N-L-α-aspartyl-L-phenylalanine methyl ester), displayclean sweet tastes very similar to that of sugar (S. G. Wiet and G. A.Miller, Food Chemistry, 58(4):305-311 (1997)). In other words, thesecompounds are not characterized as having bitter or metallicaftertastes.

However, high intensity sweeteners such as sucralose and aspartame arereported to have sweetness delivery problems, i.e., delayed onset andlingering of sweetness (S. G. Wiet, et al., J. Food Sci., 58(3):599-602,666 (1993)).

Hence, there is a need for sweet taste enhancers with desirablecharacteristics. It has been reported that an extra-cellular domain,e.g., the Venus flytrap domain of a chemosensory receptor, especiallyone or more interacting sites within the Venus flytrap domain, is asuitable target for compounds or other entities to modulate thechemosensory receptor and/or its ligands. Certain compounds includingthe compounds having structural Formula (I) have been reported to havesuperior sweet taste enhancing properties and are described in the fourpatent applications listed below.

(1) U.S. patent application Ser. No. 11/760,592, entitled “Modulation ofChemosensory Receptors and Ligands Associated Therewith”, filed Jun. 8,2007; (2) U.S. patent application Ser. No. 11/836,074, entitled“Modulation of Chemosensory Receptors and Ligands Associated Therewith”,filed Aug. 8, 2007; (3) U.S. Patent Application Ser. No. 61/027,410,entitled “Modulation of Chemosensory Receptors and Ligands AssociatedTherewith”, filed Feb. 8, 2008; and (4) International Application No.PCT/US2008/065650, entitled “Modulation of Chemosensory Receptors andLigands Associated Therewith”, filed Jun. 3, 2008. The content of theseapplications are herein incorporated by reference in their entirety forall purposes.

Accordingly, the present invention provides intermediates andprocesses/methods improving the laboratory scale syntheses of thesesweet taste enhancers and the preparation of their salts.

SUMMARY OF THE INVENTION

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

which comprises reacting a compound having structural Formula (II)

with a base or an activating reagent, wherein R¹ is —CN or —C(O)NH₂; andX is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

which comprises reacting a compound having structural Formula (III)

with NH₂S(O)₂NH₂ or Cl—S(O)₂—NH₂ optionally in the presence of a base,to provide directly the compound having structural Formula (I), oralternatively to provide the compound having structural formula (II)which is further reacted with an inorganic base or an activating reagentto provide the compound having structural Formula (I), wherein R¹ is —CNor —C(O)NH₂; and X is alkyl, substituted alkyl, alkenyl, substitutedalkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, orsubstituted heteroalkenyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

comprising reacting a compound having structural Formula (VII)

with NH₃ or NH₃.H₂O; wherein X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl; and R⁷ is a leaving groupselected from the group consisting of halo, —OMs, —OTs, and —OTf.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (Ib):

comprising reacting a compound having structural Formula (I)

with an alkali metal- or alkaline earth metal-based inorganic base,wherein M is a cation of alkali metal or alkaline earth metal; X isalkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl,substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl; nis 1, when M is a cation of alkali metal; and n is 2, when M is a cationof alkaline earth metal.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (Ia):

comprising reacting a compound having structural Formula (IIc1)

with a hydroxide or alkoxide base in an aqueous solution at atemperature ranging from about 25 to about 95° C., wherein Y is C1-C12alkylene or C1-C12 alkenylene; and R⁸ is C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIc1):

comprising adding a solution of a compound having structural Formula(IIIc1)

in a mixed solvent of methylene chloride and dimethylacetamide to asolution of Cl—S(O)₂—NH₂ in methylene chloride to form a reactionmixture, and maintaining the reaction mixture at about room temperaturefor about 6 to about 18 hours; wherein Y is C1-C12 alkylene or C1-C12alkenylene; and R⁸ is C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIc1):

comprising reacting HO—Y—C(O)—NHR⁸ with

in the presence of a base to form a first mixture solution;concentrating the first mixture solution to form a concentrated firstmixture solution, wherein the volume of the concentrated first mixturesolution is equivalent to or less than about 50% of the volume of thefirst mixture solution; diluting the concentrated first mixture solutionwith an ether to form a second mixture solution; concentrating thesecond mixture solution to form a concentrated second mixture solution,wherein the volume of the concentrated second mixture solution isequivalent to or less than about 50% of the volume of the second mixturesolution; diluting the concentrated second mixture solution with ethylacetate to form a third mixture solution, and concentrating the thirdmixture solution to form a concentrated third mixture solution; whereinY is C1-C12 alkylene or C1-C12 alkenylene; and R⁸ is C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparingsulfamoyl chloride:

comprising reacting chlorosulfonyl isocyanate with formic acid in thepresence of an organic amine.

In one embodiment, the present invention provides a process of preparinga compound having structural formula (XI):

comprising reacting a compound having structural formula (XII):

with NH₂R⁸ under a pressure higher than the standard atmosphericpressure at a temperature higher than about 80° C., wherein Y is C1-C12alkylene or C1-C12 alkenylene; and R⁸ and R¹² are independently C1-C12alkyl.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides intermediates and methods/processes forpreparing compounds having structural Formula (I) and their salts atlarge scale, such as, for example, kilogram to metric ton scale. Theadvantages of the present intermediates and methods/processes include atleast the following: (a) enabling synthesis of compounds of Formula (I)from building blocks that are commercially available in kg to metric tonquantities and at an affordable price; (b) enabling synthesis ofcompounds of Formula (I) using reagents and solvents that are compatiblewith large scale process; (c) improving overall synthesis yield todecrease overall cost as compared to the laboratory synthesis; (d)purifying intermediates using crystallization techniques instead ofchromatography on silica gel and thereby substantially reducing the timeand cost of production.

Prior to specifically describing embodiments and examples of the presentinvention, the following definitions are provided.

DEFINITIONS

“Activating reagent”, as used herein, denotes a reagent which can reactwith one of the starting materials of a chemical reaction to form one ormore active intermediate which subsequently facilitates the completionof the reaction. The active intermediate may not be stable enough to beseparated and characterized. Examples of the activating reagent include,but are not limited to the coupling reagents used in amide/peptidesynthesis, such as carbodiimide compound (EDC, DCC, DIC, and the like)and benzotriazole compounds (such as HOBt and HOAt); certain oxides andchloride (such as P₂O₅ and POCl₃); a reagent which react with a moleculeto form a leaving group (such as MSCl, Tf₂O, and reagents for Mitsunobureaction); and etc.

“Alkali metal”, as used herein, denotes a series of elements comprisingGroup 1 (IUPAC style) of the periodic table including lithium (Li),sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium(Fr). Preferably, the alkali metal is Li, Na, or K.

“Alkaline earth metal”, as used herein, denotes a series of elementscomprising Group 2 (IUPAC style) of the periodic table includingberyllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium(Ba) and radium (Ra). Preferably, the alkali metal is Mg or Ca.

“Ammonia” refers to the gas having formula NH₃ or a solution thereof.Preferably, ammonia is an aqueous solution of NH₃.

By “Alkyl”, it is meant a univalent group derived from a saturatedhydrocarbon by removing one hydrogen atom. The saturated hydrocarbon maycontain normal, secondary, or tertiary carbon atoms. These carbon atomsmay be arranged in straight or branched chain, or in cyclic ring, or acombination thereof. For example, an alkyl group can have 1 to 20 carbonatoms (i.e, C1-C20 alkyl), 1 to 12 carbon atoms (i.e., C1-C12 alkyl), or1 to 6 carbon atoms (i.e., C1-C6 alkyl). Examples of suitable alkylgroups include, but are not limited to, methyl (Me, —CH₃), ethyl (Et,—CH₂CH₃), 1-propyl (n-Pr, n-propyl, —CH₂CH₂CH₃), 2-propyl (i-Pr,i-propyl, —CH(CH₃)₂), 1-butyl (n-Bu, n-butyl, —CH₂CH₂CH₂CH₃),2-methyl-1-propyl (i-Bu, i-butyl, —CH₂CH(CH₃)₂), 2-butyl (s-Bu, s-butyl,—CH(CH₃)CH₂CH₃), 2-methyl-2-propyl (t-Bu, t-butyl, —C(CH₃)₃), 1-pentyl(n-pentyl, —CH₂CH₂CH₂CH₂CH₃), 2-pentyl (—CH(CH₃)CH₂CH₂CH₃), 3-pentyl(—CH(CH₂CH₃)₂), 2-methyl-2-butyl (—C(CH₃)₂CH₂CH₃), 3-methyl-2-butyl(—CH(CH₃)CH(CH₃)₂), 3-methyl-1-butyl (—CH₂CH₂CH(CH₃)₂), 2-methyl-1-butyl(—CH₂CH(CH₃)CH₂CH₃), 1-hexyl (—CH₂CH₂CH₂CH₂CH₂CH₃), 2-hexyl(—CH(CH₃)CH₂CH₂CH₂CH₃), 3-hexyl (—CH(CH₂CH₃)(CH₂CH₂CH₃)),2-methyl-2-pentyl (—C(CH₃)₂CH₂CH₂CH₃), 3-methyl-2-pentyl(—CH(CH₃)CH(CH₃)CH₂CH₃), 4-methyl-2-pentyl (—CH(CH₃)CH₂CH(CH₃)₂),3-methyl-3-pentyl (—C(CH₃)(CH₂CH₃)₂), 2-methyl-3-pentyl(—CH(CH₂CH₃)CH(CH₃)₂), 2,3-dimethyl-2-butyl (—C(CH₃)₂CH(CH₃)₂),3,3-dimethyl-2-butyl (—CH(CH₃)C(CH₃)₃, and octyl (—(CH₂)₇CH₃).

“Alkylene” refers to a divalent group derived from an alkyl by removingone hydrogen atom. That is, “alkylene” can be a saturated, branched orstraight chain or cyclic hydrocarbon radical having two monovalentradical centers derived by the removal of two hydrogen atoms from thesame or two different carbon atoms of a parent alkane. For example, analkylene group can have 1 to 20 carbon atoms, 1 to 12 carbon atoms, or 1to 6 carbon atoms. Typical alkylene radicals include, but are notlimited to, methylene (—CH₂—), 1,1-ethyl (—CH(CH₃)—), 1,2-ethyl(—CH₂CH₂—), 1,1-propyl (—CH(CH₂CH₃)—), 1,2-propyl (—CH₂CH(CH₃)—),1,3-propyl (—CH₂CH₂CH₂—), 1,4-butyl (—CH₂CH₂CH₂CH₂—), and the like.

“Alkenyl” refers to a univalent group derived from a hydrocarbon byremoving one hydrogen atom wherein the hydrocarbon contains at least onecarbon-to-carbon double bond. For example, an alkenyl group can have 1to 20 carbon atoms (i.e, C₁-C₂₀ alkenyl), 1 to 12 carbon atoms (i.e.,C1-C12 alkenyl), or 1 to 6 carbon atoms (i.e., C1-C6 alkenyl). Typicalalkenyl groups include, but are not limited to, ethenyl, prop-1-en-1-yl,prop-1-en-2-yl, prop-2-en-1-yl (allyl), cycloprop-1-en-1-yl;cycloprop-2-en-1-yl, but-1-en-1-yl, but-1-en-2-yl,2-methyl-prop-1-en-1-yl, but-2-en-1-yl, but-2-en-2-yl,buta-1,3-dien-1-yl, buta-1,3-dien-2-yl, cyclobut-1-en-1-yl,cyclobut-1-en-3-yl, cyclobuta-1,3-dien-1-yl, and the like.

“Alkenylene” refers to a divalent group derived from an alkenyl byremoving one hydrogen atom. That is, “alkenylene” can be an unsaturated,branched or straight chain or cyclic unsaturated hydrocarbon radicalhaving two monovalent radical centers derived by the removal of twohydrogen atoms from the same or two different carbon atoms of a parentalkene.

“Alkoxyl” refers to a monovalent radical —OR wherein R is an alkyl oralkenyl.

“Base” refers to a substance whose molecule or ion can combine with aproton (hydrogen ion), a substance capable of donating a pair ofelectrons (to an acid) for the formation of a coordinate covalent bond.A base can be inorganic or organic. Examples of base include, but arenot limited to sodium hydroxide, sodium hydride, ammonia,1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and 4-dimethylaminopyridine(DMAP).

“Halo” refers to a univalent group derived from a halogen elementincluding fluorine, chlorine, bromine, iodine, and astatine.

By “leaving group”, it is meant a functional group capable of detachingfrom a chemical substance. Examples of leaving group include, but arenot limited to alkoxy, hydroxyl, carboxylate, fluoro, chloro, bromo,iodo, azide, thiocyanate, nitro, mesylate (—OMs), tosylate (—OTs),triflate(—OTf), and etc.

“Heteroalkyl” or “heteroalkenyl” refers to alkyl or alkenyl,respectively, in which one or more of the carbon atoms (and optionallyany associated hydrogen atoms), are each, independently of one another,replaced with the same or different heteroatoms or heteroatomic groups.Similarly, “heteroalkylene,” or “heteroalkenylene” refers to alkylene oralkenylene, respectively, in which one or more of the carbon atoms (andoptionally any associated hydrogen atoms), are each, independently ofone another, replaced with the same or different heteroatoms orheteroatomic groups. Typical heteroatoms or heteroatomic groups whichcan replace the carbon atoms include, but are not limited to, —O—, —S—,—N—, —Si—, —NH—, —S(O)—, —S(O)₂—, —S(O)NH—, —S(O)₂NH— and the like andcombinations thereof. The heteroatoms or heteroatomic groups may beplaced at any interior position of the alkyl or alkenyl. Typicalheteroatomic groups which can be included in these groups include, butare not limited to, —O—, —S—, —O—O—, —S—S—, —O—S—, —N(R^(a))₂—, ═N—N═,—N═N—, —N═N—N(R^(a))₂, —P(O)₂—, —P(O)₂—, —POR^(a)—, —O—P(O)₂—, —SO—,—SO₂—, —Sn(R^(a))₂— and the like, where each R^(a) is independentlyhydrogen, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,substituted arylalkyl, cycloalkyl, substituted cycloalkyl,cycloheteroalkyl, substituted cycloheteroalkyl, heteroalkyl, substitutedheteroalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl orsubstituted heteroarylalkyl, or a protecting group.

“Protecting group” refers to a grouping of atoms that when attached to areactive functional group in a molecule masks, reduces or preventsreactivity of the functional group. Examples of protecting groups can befound in Green et al., “Protective Groups in Organic Chemistry”, (Wiley,2^(nd) ed. 1991) and Harrison et al., “Compendium of Synthetic OrganicMethods”, Vols. 1-8 (John Wiley and Sons, 1971-1996). Representativeamino protecting groups include, but are not limited to, formyl, acetyl,trifluoroacetyl, benzyl, benzyloxycarbonyl (“CBZ”), tert-butoxycarbonyl(“Boc”), trimethylsilyl (“TMS”), 2-trimethylsilyl-ethanesulfonyl(“SES”), trityl and substituted trityl groups, allyloxycarbonyl,9-fluorenylmethyloxycarbonyl (“FMOC”), nitro-veratryloxycarbonyl(“NVOC”) and the like. Representative hydroxy protecting groups include,but are not limited to, those where the hydroxy group is either acylatedor alkylated such as benzyl, and trityl ethers as well as alkyl ethers,tetrahydropyranyl ethers, trialkylsilyl ethers and allyl ethers.

The term “substituted”, when used to modify a specified group orradical, means that one or more hydrogen atoms of the specified group orradical are each, independently of one another, replaced with the sameor different substituent(s). Substituent groups useful for substitutingsaturated carbon atoms in the specified group or radical include, butare not limited to —R′, halo, —O⁻, ═O, —OR^(b), —SR^(b), —S⁻, ═S,—N(R^(d))₂, ═NR^(b), ═N—OR^(b), trihalomethyl, —CF₃, —CN, —OCN, —SCN,—NO, —NO₂, ═N₂, —N₃, —S(O)₂R^(b), —S(O)₂NR^(b), —S(O)₂O⁻, —S(O)₂OR^(b),—OS(O)₂R^(b), —OS(O)₂O⁻, —OS(O)₂OR^(b), —P(O)(O⁻)₂, —P(O)(OR^(b))(O⁻),—P(O)(OR^(b))(OR^(b)), —C(O)R^(b), —C(S)R^(b), —C(NR^(b))R^(b), —C(O)O⁻,—C(O)OR^(b), —C(S)OR^(b), —C(O)N(R^(d))₂, —C(NR)N(R^(d))₂, —OC(O)R^(b),—OC(S)R^(b), —OC(O)O⁻, —OC(O)OR^(b), —OC(S)OR^(b), —NR^(b)C(O)R^(b),—NR^(b)C(S)R^(b), —NR^(b)C(O)O⁻, —NR^(b)C(O)OR^(b), —NR^(b)C(S)OR^(b),—NR^(b)C(O)N(R^(d))₂, —NR^(b)C(NR^(b))R^(b) and—NR^(b)C(NR^(b))N(R^(d))₂, where R^(c) is selected from the groupconsisting of alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl, aryl,arylalkyl, heteroaryl and heteroarylalkyl; each R^(b) is independentlyhydrogen, a protecting group, or R^(c); and each R^(d) is independentlyR^(b) or alternatively, the two R^(d)s may be taken together with ° thenitrogen atom to which they are bonded form a 4-, 5-, 6- or 7-memberedcycloheteroalkyl which may optionally include from 1 to 4 of the same ordifferent additional heteroatoms selected from the group consisting ofO, N and S. As specific examples, —N(R^(d))₂ is meant to include —NH₂,—NH-alkyl, N-pyrrolidinyl and N-morpholinyl. As another specificexample, a substituted alkyl is meant to include -alkylene-O-alkyl,-alkylene-heteroaryl, -alkylene-cycloheteroalkyl, -alkylene-C(O)OR^(b),-alkylene-C(O)N(R^(d))₂, and —CH₂—CH₂—C(O)—CH₃. The one or moresubstituent groups, taken together with the atoms to which they arebonded, may form a cyclic ring including cycloalkyl andcycloheteroalkyl.

The term “alcohol” herein means an organic compound in which a hydroxylgroup (—OH) is bound to a carbon atom of an alkyl or substituted alkylgroup. The alcohol includes primary, secondary, and tertiary alcohols.Examples of alcohol include, but are not limited to, methanol, ethanol,n-propanol, isopropanol, n-butanol, s-butanol, and t-butanol. Thealcohol may be further optionally substituted.

The term “alkane hydrocarbon” herein means an organic compound or amixture of organic compounds which consist of hydrogen and carbon andcontain no or trace amount of unsaturated carbon-carbon bond. Examplesof alkane hydrocarbon include, but are not limited to, hexanes andheptanes.

The term “base” refers to a substance that can accept protons. Examplesof the base include, but are not limited to sodium hydride (NaH),potassium hydride (KH), sodium hexamethyldisilazane (NaHMDS), potassiumhexamethyldisilazane (KHMDS), sodium tert-butoxide (NaO^(t)Bu),potassium tert-butoxide (KO^(t)Bu), sodium hydroxide, potassiumhydroxide, calcium hydroxide, sodium methoxide, sodium ethoxide, sodiumtert-butoxide, and a mixture thereof. The term “hydroxide or alkoxidebase” refers to a base, the disassociation of which produces the anionOH⁻ or RO⁻, where R is an alkyl group. Examples of the hydroxide baseinclude, but are not limited to, sodium hydroxide, potassium hydroxide,calcium hydroxide, and a mixture thereof. Examples of the alkoxide baseinclude, but are not limited to, sodium methoxide, sodium ethoxide,sodium tert-butoxide, and a mixture thereof.

By “room temperature”, it is meant the normal temperature of room inwhich people live or conduct business. In one example, the roomtemperature denotes a temperature ranging from about 20 to about 25° C.

As used herein, “polar aprotic solvent” refers to a solvent that sharesion dissolving power with a protic solvent but lack an acidic hydrogen.A protic solvent is a solvent that has a hydrogen atom bound to anoxygen as in a hydroxyl group or a nitrogen as in an amine group. Moregenerally, any molecular solvent which contains dissociable H⁺, such ashydrogen fluoride, is called a protic solvent. The molecules of suchprotic solvents can donate an H⁺ (proton). Conversely, aprotic solventscannot donate hydrogen. The aprotic solvents generally have highdielectric constants and high polarity. Examples are dimethyl sulfoxide(DMSO), dimethylformamide (DMF), dioxane, hexamethylphosphorotriamide(HMPTA), and tetrahydrofuran (THF).

The term “organic amine” herein denotes a compound having structuralformula N(R)₃, wherein each R is independently hydrogen, alkyl, alkenyl,aryl, heteroaryl, heteroalkyl, arylalkyl, or heteroarylalkyl, oralternatively, two of R, together with the nitrogen atom to which theyare attached, form a heterocyclic ring. Examples of organic amineinclude, but are not limited to, methylamine, dimethylamine,diethylamine, methylethylamine, triethylamine, diisoproylethylamine(DIEA), morpholine, peperidine, and combinations thereof.

The term “portionwise”, as used herein, describes a controlled dischargeof a substance for adding to another substance or filling a reactor orcontainer. The controlled discharge may be discrete or continuous. Theportionwise discharge of a substance may include discharge the substancein one portion or in multiple portions. In one example, a liquid isadded to a reaction mixture over an extended period of time bycontrolling the discharging speed of the liquid. In another example, asolid material is added to a reaction mixture by dividing the solidmaterial in multiple portions and discharge the solid material oneportion at a time.

Processes/Methods

The present invention provides methods/processes for preparing thecompounds having structural Formula (I) amenable to large scale process.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

which comprises reacting a compound having structural Formula (II)

with abase or an activating reagent, wherein R¹ is —CN or —C(O)NH₂; andX is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl. For example, this process may comprise reacting acompound having structural Formula (IIa)

with an activating reagent to provide the compound of Formula (I).Alternatively, this process may comprise reacting a compound havingstructural Formula (IIb)

with a base to provide the compound of Formula (I).

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

which comprises reacting a compound having structural Formula (III)

with NH₂S(O)₂NH₂ or Cl—S(O)₂—NH₂ optionally in the presence of a base,to provide directly the compound having structural Formula (I), oralternatively to provide the compound having structural formula (II) ofclaim 1 which is further reacted with an inorganic base or an activatingreagent to provide the compound having structural Formula (I), whereinR¹ is —CN or —C(O)NH₂; and X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl. For example, this processmay comprise reacting a compound having structural Formula (IIIa):

with NH₂—S(O)₂—NH₂ in the presence of a base to provide the compound ofFormula (I). Alternatively, this process may comprise reacting acompound having structural Formula (Ma)

with Cl—S(O)₂—NH₂ to provide a compound having structural Formula (IIb)

which is further reacted with a base to provide the compound havingstructural Formula (I). Alternatively, this process may comprisereacting a compound having structural Formula (IIIb)

with Cl—S(O)₂—NH₂ to provide a compound having structural Formula (IIa),

which is further reacted with an activating reagent to provide thecompound having structural Formula (I).

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIb):

which comprises hydrolyzing a compound having structural formula (IIIa)

wherein X is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIb):

which comprises treating a compound having structural formula (IIIc)with ammonia,

wherein X is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl; and R³ is halo or alkoxyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIa):

which comprises reducing a compound having structural Formula (IV), ortreating a compound having structural Formula (IV) with ammonia,

wherein R⁴ is nitro or halo; and X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl. For example, this processmay comprise reducing the compound having structural Formula (IV) toprovide the compound of Formula (IIIa), wherein R⁴ is nitro.Alternatively, the process may comprise treating the compound havingstructural Formula (IV) with ammonia to provide the compound of Formula(IIIa), wherein R⁴ is halo.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IV):

comprising reacting a compound having structural Formula (V)

with X—OH in the presence of a base; wherein R⁴ is nitro, —NH₂, or halo;X is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl; and R⁵ is nitro or halo.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IV):

comprising reacting a compound having structural Formula (VI)

with X—R⁶ in the presence of a base or an activating reagent; wherein R⁴is nitro, —NH₂, or halo; X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl; and R⁶ is a leaving groupselected from halo, —OMs, —OTs, and —OTf.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (I):

comprising reacting a compound having structural Formula (VII)

with NH₃ or NH₃.H₂O; wherein X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl; and R⁷ is a leaving groupselected from the group consisting of halo, —OMs, —OTs, and —OTf.

In preferred embodiments of the above described processes, X is C1-C12alkyl, C1-C12 heteroalkyl, C1-C12 alkenyl, C1-C12 heteroalkenyl,—Y—C(O)—OR²², or —Y—C(O)—NH—R²; Y is C1-C12 alkylene or C1-C12alkenylene; and each R² is independently hydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (Ia):

comprising reacting a compound having structural Formula (VIII)

with R⁸—NH₂, in the presence of an activating reagent; wherein Y isC1-C12 alkylene or C1-C12 alkenylene; R⁸ is C1-C12 alkyl; and R⁹ ishydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIc):

comprising reacting a compound having structural Formula (IX)

with R⁸—NH₂, in the presence of an activating reagent; wherein R¹ is —CNor —C(O)NH₂; each R² is independently hydrogen or C1-C12 alkyl; Y isC1-C12 alkylene or C1-C12 alkenylene; R⁸ is C1-C12 alkyl; and R⁹ ishydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIc):

comprising reacting a compound having structural Formula (X)

with R⁸—NH₂, in the presence of an activating reagent; wherein R¹ is —CNor —C(O)NH₂; Y is C1-C12 alkylene or C1-C12 alkenylene; and R⁸ is C1-C12alkyl; and R⁹ is hydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a process of preparinga compound having a structural formula of R⁶—Y—C(O)—NH—R² comprisingreacting a compound having a structural formula of R⁶—Y—C(O)—R¹⁰ withR²—NH₂, optionally in the presence of an activating reagent or a base;wherein R² is hydrogen or C1-C12 alkyl; R⁶ is halo or hydroxyl; Y isC1-C12 alkylene or C1-C12 alkenylene; R¹⁰ is a leaving group selectedfrom the group consisting of halo, —OR¹¹, —O—C(═CH₂)—OR¹², and

R¹¹ is hydrogen or C1-C12 alkyl; and R¹² is C1-C12 alkyl.

In preferred embodiments of the above described processes, the compoundhaving structural Formula (I) is

In one embodiment, the present invention provides syntheses of thesodium salt of the compounds having structural Formula (I) amenable tolarge scale process. It was observed that the sodium salts of thepresent compounds have improved physical properties especially withregard to improved solubility characteristics in specific solvents thatare used to prepare stock solutions.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (Ib):

comprising reacting a compound having structural Formula (I)

with an alkali metal- or alkaline earth metal-based inorganic base,wherein M is a cation of alkali metal or alkaline earth metal; X isalkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl,substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl; nis 1, when M is a cation of alkali metal; and n is 2, when M is a cationof alkaline earth metal. It is preferable that M is a cation of sodium.It is also preferable that X is C1-C12 alkyl, C1-C12 heteroalkyl, C1-C12alkenyl, C1-C12 heteroalkenyl, —Y—C(O)—OR², or —Y—C(O)—NH—R²; Y isC1-C12 alkylene or C1-C12 alkenylene; and each R² is independentlyhydrogen or C1-C12 alkyl.

In one embodiment of the above described processes, X is selected fromthe group consisting of —CH₃, —CH₂CH₃, —CH₂CH₂CH₃, —CH(CH₃)₂,—CH₂CH₂CH₂CH₃, —CH₂CH(CH₃)₂, —C(CH₃)₃, —CH₂CH₂CH₂CH₂CH₃, —CH₂C(CH₃)₂CH₃,—C(CH₃)₂CH₂CH₃, —CH₂CH₂CH(CH₃)₂, —CH₂CH₂CH₂CH₂CH₂CH₃, —CH₂C(CH₃)₂CH₂CH₃,—CH₂CH₂C(CH₃)₂CH₃, —CH₂CH₂CH₂CH(CH₃)₂, —CH₂CH(CH₂CH₃)CH₂CH₃,—CH₂CH₂OCH₃, —CH₂CH₂CH₂OCH₃, —CH₂CH₂CH₂OCH₂CH₃, and—CH₂CH₂CH₂CH₂OCH₂CH₃.

In preferred embodiments of the above described processes, the compoundhaving structural Formula (Ib) is

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (Ia):

comprising reacting a compound having structural Formula (IIc1)

with a hydroxide or alkoxide base in an aqueous solution at atemperature ranging from about 25 to about 95° C., wherein Y is C1-C12alkylene or C1-C12 alkenylene; and R⁸ is C1-C12 alkyl. In one specificembodiment, the hydroxide base is sodium hydroxide, potassium hydroxide,or a mixture thereof. In one embodiment, the reaction is carried out ata temperature ranging from about 35 to about 85° C. In one embodiment,the reaction is carried out at a temperature ranging from about 40 toabout 70° C. Depending on the reaction conditions, such as temperature,scale, and concentration of the reaction mixture, the reaction may becarried out in about 4 to about 24 hours. In one embodiment, thereaction is carried out in about 8 to about 12 hours. In anotherembodiment, the reaction further comprises adding an alcohol to thereaction mixture of the compound having structural Formula (IIc1) andthe hydroxide base to form an aqueous-alcohol mixture; and adding ahydrochloride solution to the aqueous-alcohol mixture to adjust the pHthereof to a range from about 4 to about 5. In one specific embodiment,the alcohol is methanol, ethanol, propanol, or a mixture thereof. In oneembodiment, the hydrochloride solution is an aqueous solution. In oneembodiment, the pH of the aqueous-alcohol mixture is adjusted to about4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8 or 4.9. In another embodiment,the reaction mixture of the compound having structural Formula (IIc1)and the hydroxide base is washed with an ether prior to the addition ofthe alcohol. Examples of the ether include, but are not limited to,dimethylether, diethylether, diisopropylether, di-tert-butyl ether,methyl tert-butyl ether, or a mixture thereof. In one specificembodiment, the compound having structural formula (Ia) is

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIc1):

comprising adding a solution of a compound having structural Formula(IIIc 1)

in a mixed solvent of methylene chloride and dimethylacetamide to asolution of Cl—S(O)₂—NH₂ (sulfamoyl chloride) in methylene chloride toform a reaction mixture; maintaining the reaction mixture at about roomtemperature for about 6 to about 18 hours; and extracting the reactionmixture with an aqueous solution of a hydroxide or alkoxide base to forman extracted basic solution wherein the compound having structuralformula (Het) is stabilized; wherein Y is C1-C12 alkylene or C1-C12alkenylene; and R⁸ is C1-C12 alkyl. In one embodiment, the hydroxide oralkoxide base is sodium hydroxide or potassium hydroxide. The volumeratio of methylene chloride and dimethylacetamide in the mixed solventcan be from about 1:100 to about 100:1. In one embodiment, methylenechloride and dimethylacetamide in the mixed solvent is in a ratioranging from about 3:1 to about 30:1. In another embodiment, methylenechloride and dimethylacetamide in the mixed solvent is in a ratioranging from about 4:1 to about 25:1. In another embodiment, methylenechloride and dimethylacetamide in the mixed solvent is in a ratioranging from about 5:1 to about 20:1. In another embodiment, methylenechloride and dimethylacetamide in the mixed solvent is in a ratioranging of about 16:1. In one embodiment, during addition of thesolution of a compound having structural Formula (IIIc1) to the solutionof CI—S(O)₂—NH₂, the reaction mixture is maintained at a temperatureranging from about −5 to about 15° C. with the range from about 0 toabout 10° C. more preferred. In one embodiment of the reaction, thesolvent for the solution of Cl—S(O)₂—NH₂ is methylene chloride. Inanother embodiment, the solution of Cl—S(O)₂—NH₂ is in a mixed solventof methylene chloride and acetonitrile. In one embodiment, the volumeratio of methylene chloride and acetonitrile ranges from about 5:1 toabout 1:1. In another embodiment, the volume ratio of methylene chlorideand acetonitrile ranges from about 4:1 to about 2:1. In one embodiment,after the reaction mixture of the compound having structural Formula(IIIc1) and Cl—S(O)₂—NH₂ is maintained at the room temperature for about6 to about 18 hours and/or prior to the extraction of the reactionmixture with an aqueous solution of a hydroxide or alkoxide base, thereaction mixture is quenched with an aqueous solution of NaHCO₃. Thatis, an aqueous solution of NaHCO₃ is mixed with the reaction mixture toform a quenched mixture. The quenched mixture is maintained at atemperature of about 45° C. or below during the mixing process. In oneembodiment, the temperature is maintained in a range from about 5 toabout 35° C. with the range from about 10 to about 30° C. morepreferred. In one embodiment, the aqueous solution of NaHCO₃ is asaturated aqueous solution of NaHCO₃. The mixing process may be carriedout by adding the aqueous solution of NaHCO₃ to the reaction mixture oradding the reaction mixture to the aqueous solution of NaHCO₃.

In one embodiment, the present invention provides a process of preparinga compound having structural Formula (IIIc1):

comprising reacting HO—Y—C(O)—NHR⁸ with 2-amino-6-fluorobenzonitrile ina polar aprotic solvent in the presence of a base to form a firstmixture solution; concentrating the first mixture solution to form aconcentrated first mixture solution, wherein the volume of theconcentrated first mixture solution is equivalent to or less than about50% of the volume of the first mixture solution; diluting theconcentrated first mixture solution with an ether to form a secondmixture solution; concentrating the second mixture solution to form aconcentrated second mixture solution, wherein the volume of theconcentrated second mixture solution is equivalent to or less than about50% of the volume of the second mixture solution; diluting theconcentrated second mixture solution with ethyl acetate to form a thirdmixture solution; and concentrating the third mixture solution to form aconcentrated third mixture solution; wherein Y is C1-C12 alkylene orC1-C12 alkenylene; and R⁸ is C1-C12 alkyl. In one embodiment, the polaraprotic solvent is THF. Examples of the base include, but are notlimited to sodium hydride (NaH), potassium hydride (KH), sodiumhexamethyldisilazane (NaHMDS), potassium hexamethyldisilazane (KEMDS),sodium tert-butoxide (NaO^(t)Bu), potassium tert-butoxide (KO^(t)Bu),and a mixture thereof. Examples of the ether include, but are notlimited to, dimethylether, diethylether, diisopropylether, di-tert-butylether, methyl tert-butyl ether, or a mixture thereof. In one embodiment,the reaction of HO—Y—C(O)—NHR⁸ with 2-amino-6-fluorobenzonitrile iscarried out by mixing HO—Y—C(O)—NHR⁸ with the base to form a reactivemixture, and then mixing the reactive mixture with2-amino-6-fluorobenzonitrile. In one embodiment, the molar ratio ofHO—Y—C(O)—NHR⁸ to the base ranges from about 1:1 to about 2:1. Inanother embodiment, the molar ratio of HO—Y—C(O)—NHR⁸ to the base rangesfrom about 1.2:1 to about 1.8:1. In another embodiment, the molar ratioof HO—Y—C(O)—NHR⁸ to the base is about 1.5:1. In one embodiment, theabove concentration steps are carried out by evaporating the solvent.The evaporation can be accomplished by any means known to one skilled inthe art including, but are not limited to applying vacuum to thereaction mixture, elevating temperature of the reaction mixture,spinning the reaction mixture on a solid surface, stirring the reactionmixture, blowing air or other gas to the surface of the reactionmixture, and any combination thereof. Preferably, the temperature of themixture solution during the evaporation process is not higher than about50° C. In one embodiment, the evaporation is accomplished by rotovapingthe reaction mixture at a temperature of about 50° C. or below with thetemperature of about 40° C. or below more preferred. In one embodiment,the volume of any of the concentrated first, second, and third mixturesolutions is equivalent to or less than about 45% of the volume of thefirst, second, and third mixture solutions, respectively. In oneembodiment, the volume of any of the concentrated first, second, andthird mixture solutions is equivalent to or less than about 35% of thevolume of the first, second, and third mixture solutions, respectively.In one embodiment, the volume of any of the concentrated first, second,and third mixture solutions is equivalent to or less than about 30% ofthe volume of the first, second, and third mixture solutions,respectively. In one embodiment, the compound having structural Formula(IIIc1) precipitates out from the concentrated third mixture solution assolids. In one embodiment, the concentrated third mixture solution isdiluted with an alkane hydrocarbon, and the solids of the compoundhaving structural Formula (IIIc1) are filtered and washed with thealkane hydrocarbon. Examples of the alkane hydrocarbon include, but arenot limited to, hexanes, heptanes, and mixtures thereof. In anotherembodiment, the second mixture solution is washed with water or anaqueous solution prior to the concentration of the second mixturesolution.

In one embodiment, the present invention provides a process of preparingsulfamoyl chloride comprising reacting chlorosulfonyl isocyanate withformic acid in the presence of an organic amine. Examples of the organicamine include, but are not limited to, methylamine, dimethylamine,diethylamine, methylethylamine, triethylamine, diisoproylethylamine(DIEA), morpholine, peperidine, and combinations thereof. The chemicalstructures of sulfamoyl chloride, chlorosulfonyl isocyanate, and formicacid are shown below:

In one embodiment, the reaction comprises portionwise adding a firstmixture of formic acid and the organic amine to a second mixture ofchlorosulfonyl isocyanate and the organic amine to form a reactionmixture. In one embodiment, the molar ratio of formic acid to theorganic amine is from about 200:1 to about 10:1, and the molar ratio ofchlorosulfonyl isocyanate to the organic amine is from about 200:1 toabout 10:1. In another embodiment, the molar ratios of formic acid tothe organic amine and chlorosulfonyl isocyanate to the organic amine areindependently from about 150:1 to about 15:1. In another embodiment, themolar ratios of formic acid to the organic amine and chlorosulfonylisocyanate to the organic amine are independently from about 100:1 toabout 20:1. In one embodiment, the above first and second mixtures areindependent in an organic solvent. In one specific embodiment, the abovefirst and second mixtures are both in methylene chloride. In oneembodiment, the reaction mixture is maintained at a temperature nothigher than about 50° C. In another embodiment, the reaction mixture ismaintained at a temperature ranging from about 0° C. to about 50° C. Inanother embodiment, the reaction mixture is maintained at a temperatureranging from about 10° C. to about 50° C. In another embodiment, thereaction mixture is maintained at a temperature ranging from about roomtemperature to about 50° C. In another embodiment, the reaction mixtureis maintained at a temperature ranging from about 30° C. to about 45° C.

The reaction of converting chlorosulfonyl isocyanate to sulfamoylchloride forms CO and CO₂ gas. Thus, depending on the scale of thereaction, the reaction process may be monitored and controlled. Thereaction process can be monitored and controlled by any monitoring orcontrolling methods known to one skilled in the art including bothinstrumental and visual methods. In one embodiment, the first mixture isadded to the second mixture in multiple portions, wherein the multipleportions comprise an initial portion and one or more subsequentportions, and each subsequent portion of the first mixture is not addedto the second mixture until the reaction mixture ceases forming CO₂ gas.In one embodiment, the formation of CO₂ gas is monitored by a gaschromatograph (GC) method. In another embodiment, the formation of CO₂gas is monitored by detecting the temperature change of the reaction. Inanother embodiment, the formation of CO₂ gas is monitored by visualobservation. In another embodiment, the formation of CO₂ gas ismonitored by a combination of GC, temperature detection, and visualobservation.

In one embodiment, the present invention provides a process of preparinga compound having structural formula (XI):

comprising reacting a compound having structural formula (XII):

with NH₂R⁸ under a pressure higher than the standard atmosphericpressure at a temperature higher than about 80° C., wherein Y is C1-C12alkylene or C1-C12 alkenylene; and R⁸ and R¹² are independently C1-C12alkyl. The pressurized condition can be created by any methods known toone skilled in the art. In one embodiment, the pressurized condition iscreated by running the reaction in a sealed reactor with heat. Inanother embodiment, the pressurized condition is created by pressurizingthe reactor to a desired pressure with nitrogen. In one embodiment, thereaction was conducted at a temperature ranging from about 90° C. toabout 200° C. In another embodiment, the reaction was conducted at atemperature ranging from about 100° C. to about 150° C. In anotherembodiment, the reaction was conducted at a temperature of about 120° C.In one embodiment, the reaction was conducted under a pressure of about600 psig or below. In another embodiment, the reaction was conductedunder a pressure of about 500 psig or below. In another embodiment, thereaction was conducted under a pressure of about 400 psig or below. Inanother embodiment, the reaction was conducted in a sealed reactor at atemperature of about 120° C. In one embodiment, the molar ratio of NH₂R⁸to a compound having structural formula (XI) is from about 1:1 to about2:1. In another embodiment, the molar ratio of NH₂R⁸ to a compoundhaving structural formula (XI) is from about 1.2:1 to about 1.8:1. Inanother embodiment, the molar ratio of NH₂R⁸ to a compound havingstructural formula (XI) is about 1.5:1.

In one embodiments of the above described processes, Y is selected fromthe group consisting of —CH₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, —C(CH₃)₂—,—CH₂CH₂CH₂CH₂—, —CH₂C(CH₃)₂—, —CH₂CH₂CH₂CH₂CH₂—, —CH₂C(CH₃)₂CH₂—,—C(CH₃)₂CH₂CH₂—, —CH₂CH₂C(CH₃)₂—, —CH₂CH₂CH₂CH₂CH₂CH₂—,—CH₂C(CH₃)₂CH₂CH₂—, —CH₂CH₂C(CH₃)₂CH₂—, —CH₂CH₂CH₂C(CH₃)₂—, and—CH₂CH(CH₂CH₃)CH₂CH₂—.

In one embodiment of the above described processes, R⁸ is methyl, ethyl,propyl, butyl, pentyl, or hexyl.

Intermediates

The present invention also provides synthetic intermediates forpreparing the compounds having structural Formula (I) amenable to largescale process.

In one embodiment, the present invention provides a compound havingstructural Formula (II)

wherein R¹ is —CN, —C(O)OR², or —C(O)NH₂; X is alkyl, substituted alkyl,alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl; and R² is hydrogen orC1-C12 alkyl.

In one embodiment, the present invention provides a compound havingstructural Formula (III):

wherein R¹ is —CN, —C(O)OR², or —C(O)N(R²)₂; X is alkyl, substitutedalkyl, alkenyl, substituted alkenyl, heteroalkyl, substitutedheteroalkyl, heteroalkenyl, or substituted heteroalkenyl; and each R² isindependently hydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a compound havingstructural Formula (IV):

wherein R⁴ is nitro, —NH₂, or halo; and X is alkyl, substituted alkyl,alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl.

In one embodiment, the present invention provides a compound havingstructural Formula (VII):

wherein X is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl; and R⁷ is a leaving group selected from the groupconsisting of halo, —OMs, —OTs, and —OTf.

In preferred embodiments of the above described compounds, X is C1-C12alkyl, C1-C12 heteroalkyl, C1-C12 alkenyl, C1-C12 heteroalkenyl,—Y—C(O)—OR², or —Y—C(O)—NH—R²; Y is C1-C12 alkylene or C1-C12alkenylene; and each R² is independently hydrogen or C1-C12 alkyl.

In one embodiment, the present invention provides a compound having astructural formula of R⁶—Y—C(O)—NH—R², wherein R² is hydrogen or C1-C12alkyl; and R⁶ is halo or hydroxyl.

In preferred embodiments of the above described compounds, X is selectedfrom the group consisting of —CH₃, —CH₂CH₃, —CH₂CH₂CH₃, —CH(CH₃)₂,—CH₂CH₂CH₂CH₃, —CH₂CH(CH₃)₂, —C(CH₃)₃, —CH₂CH₂CH₂CH₂CH₃, —CH₂C(CH₃)₂CH₃,—C(CH₃)₂CH₂CH₃, —CH₂CH₂CH(CH₃)₂, —CH₂CH₂CH₂CH₂CH₂CH₃, —CH₂C(CH₃)₂CH₂CH₃,—CH₂CH₂C(CH₃)₂CH₃, —CH₂CH₂CH₂CH(CH₃)₂, —CH₂CH(CH₂CH₃)CH₂CH₃,—CH₂CH₂OCH₃, —CH₂CH₂CH₂OCH₃, —CH₂CH₂CH₂OCH₂CH₃, and—CH₂CH₂CH₂CH₂OCH₂CH₃.

In preferred embodiments of the above described compounds, Y is selectedfrom the group consisting of —CH₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, —C(CH₃)₂—,—CH₂CH₂CH₂CH₂—, —CH₂C(CH₃)₂—, —CH₂CH₂CH₂CH₂CH₂—, —CH₂C(CH₃)₂CH₂—,—C(CH₃)₂CH₂CH₂—, —CH₂CH₂C(CH₃)₂—, —CH₂CH₂CH₂CH₂CH₂CH₂—,—CH₂C(CH₃)₂CH₂CH₂—, —CH₂CH₂C(CH₃)₂CH₂—, —CH₂CH₂CH₂C(CH₃)₂—, and—CH₂CH(CH₂CH₃)CH₂CH₂—.

Specific Embodiments

The following examples and schemes are provided to illustrate theprocesses/methods and intermediates for preparing compounds of thepresent invention.

In one embodiment of the present invention, the compound havingstructural formula (I) or formula (Ia) is compound 9 below:

One approach to the synthesis of 9 (scheme 1) requires 4 steps startingfrom commercially available 3-hydroxy-2,2-dimethylpropanoic acid (1).The acid 1 is first coupled to the amine 2 using conventional couplingreaction to provide the amide 3 that is further reacted with2-amino-6-fluorobenzonitrile 4 (Chimia 2006, 60, 584) to give the2-amino nitrile derivative 5. Treatment of 5 with sulfamoyl chloride 7,prepared from chlorosulfonyl isocyanate 6 (Brodsky, B. H.; Bois, J. D.J. Am. Chem. Soc. 2005, 127, 15391.), provides the sulfamoylaminoderivative 8 that is further cyclized to 9 in the presence of NaOH.

In one embodiment of Scheme 1, different bases were evaluated for theconversion of compound 3 to compound 5. These bases are NaH (60%dispersion in mineral oil), NaHMDS (1M in THF), KO^(t)Bu (1M in THF)using THF as the solvent, and K₂CO₃ using DMF as the solvent. In onespecific example, the number of equivalents of NaH was evaluated bymonitoring the reaction by GC. It was determined that 1.7 equivalents ofNaH was the preferred amount of base with this reaction typically beingheated at reflux overnight. Work-up of the reaction was alsoinvestigated. One approach was to remove about ⅔ of the THF bydistillation then dilute back to the original volume with MTBE andconduct two water washes, so that the pH of the 2^(nd) wash was 10-11.Solvent swapping into EtOAc could then be done followed by concentrationand precipitation with hexanes. The ratio of EtOAc to hexanes is fromabout 5 volumes of EtOAC to about 10 to 15 volumes of hexanes.

Due to the large amount of gas that can be instantaneously generatedwhen reacting chlorosulfonyl isocyanate (CSI) with formic acid, anextensive safety evaluation was conducted. In one embodiment of Scheme1, evaluation of this reaction using triethylamine as an additive wasconducted, particularly under certain diluted conditions, such as e.g.,CSI (1 equivalent) mixed with CH₂Cl₂ (15.6 volumes) and heated at 42°C., then added HCOOH (1.02 equivalents) containing Et₃N. Varying amountsof triethylamine were added 1, 2, 3 and 5 mol % and the rate of gasevolution was measured. It was determined that 5 mol % was the preferredamount to use as this gave a more instantaneous reaction once theinitial charge of formic acid had been consumed. Differentconcentrations were also investigated and it was shown that the reactioncould be operated successfully between 2.2 volumes of CH₂Cl₂ and 15.6volumes of CH₂Cl₂ maintaining the equivalents of CSI and HCOOH at 1:1.02and varying amounts of triethylamine from 1-5 mol %. Dilution of theformic acid solution with CH₂Cl₂ up to 1 volume was also successfullydemonstrated and adopted for scale up so that a more accurate control ofthe amount of each aliquot added could be achieved. Since there was aninitiation period being observed for the chlorosulfonyl isocyanatereaction, a method for determining when the aliquot had completelyreacted was required so as to avoid any potential accumulation whichcould have adverse safety consequences. After the aliquot is consumedgas evolution could easily be observed by foaming of the reactionmixture along with a noticeable endotherm. A reaction was run looking atdifferent ways of monitoring the reaction. In the laboratory the ReactIRappeared to be a plausible tool for monitoring the reaction. Othermethods investigated include FTIR and direct injection massspectroscopy. Another method involved taking a sample of the gas andinjecting it on the GC (using a TCD detector) looking for CO and CO₂.Since a standard of CO₂ was readily at hand this was injected and CO₂gas evolution was confirmed with another peak being seen which wasbelieved to be CO. This GC method was then further evaluated by carryingout the reaction with a constant N₂ flow. In summary, the reaction ofchlorosulfonyl isocyanate with formic acid could be monitored avoidingany accumulation and the adverse consequences thereof.

In one embodiment of Scheme 1, the reaction of converting compound 5 tocompound 8 was conducted using a solvent selected from methylenechloride, a mixture of methylene chloride and dimethylacetamide, amixture of methylene chloride and acetonitrile, or a combinationthereof. For example, a mixture of methylene chloride anddimethylacetamide with the volume ratio of 8 to 0.5 was used as asolvent for the reaction. In another example, acetonitrile was added tothe methylene chloride solution of compound 7 prior to mixing thesolution of compound 7 with the solution of compound 5. The mixingprocess could be carried out by either adding compound 7 to compound 5or adding compound 5 to compound 7. In one example, after the reactionwas finished, the reaction mixture was quenched with saturated NaHCO₃solution. After quenching with saturated NaHCO₃ solution, compound 8 wasextracted from the CH₂Cl₂ solution using 5 equivalents of a 1N NaOHsolution followed by a back extraction of the organic layer with 0.67equivalents of a 1N NaOH solution. This gave a solution of compound 8 inaqueous NaOH.

In one embodiment of Scheme 1, the cyclization of compound 8 wasperformed under aqueous conditions. Preferably, the NaOH solution ofcompound 8 was washed with MTBE prior to the cyclization reaction.Various temperatures (r.t., 45° C., 65° C. and 80° C.) were investigatedfor the cyclization. In one example, the cyclization was carried out byfirst washing the NaOH solution of compound 8 with MTBE, which wasfollowed by addition of EtOH and then acidification with HCl toprecipitate compound 9. The reaction yield and purity of compound 9based on the solid precipitates could be adjusted by adding differentamounts of EtOH. Then, purification of the precipitates (crude compound9) was investigated. The preferred approach was to slurry the crudematerial in a 50:50 mixture of EtOH/water at 80° C. for 2 hours and thencool to ambient temperature, filter and wash.

As shown by Scheme 2 below, commercially available methyl3-hydroxy-2,2-dimethylpropanoate (10) can be easily converted to amide 3by treatment with neat amine 2 at elevated temperatures and/orpressurized condition. In one embodiment, preparation of compound 3 fromcompounds 1 and 2 is conducted at a pressurized condition. Experimentswere conducted using a 300 mL Parr reactor to evaluate the reaction at atemperature lower than 200° C. Initial conditions of pressurizing thereactor to 400 psig with nitrogen and then heating it to 120° C. gavecomplete conversion within 24 h. The pressure generated when operatingunder these conditions exceeded 600 psig which was above what the 5-Galreactor can currently operate at safely, given the rating of the ventlines (this being not greater than 500 psig total). A variety ofconditions for the pressure reaction of methyl3-hydroxy-2,2-dimethylpropanoate 1 with n-propylamine 2 (1 or 1.5equivalents) were then investigated with and without pressurizing thereactor with nitrogen. One of the preferred reaction conditions was torun the reaction at 120° C. without any additional nitrogen pressureusing 1.5 equivalents of n-propylamine. Concentration of this materialusing toluene as a solvent to azeotropically remove the methanolby-product, as well as the excess n-propylamine was then conducted. Thisgave 3 as a viscous oil which was typically used as is, but it wasobserved that upon standing, this material would begin to crystallize.

Other methods can be used to improve the synthesis of the amide 3 toobtain a process that is scalable (for a review see Tetrahedron 61(2005) 10827-10852). This includes the use of other coupling reagents,other esters or the use of an activated carboxylic acid 1, such as, forexample, acyl chloride or fluoride 1a, mixed anhydride 1b, ethoxyvinylester 1c, acyloxyboronate 1d (Scheme 3).

The amide 3 can also be reacted with 2,4-dinitrobenzonitrile 11 usingNaH, potassium tert-butoxide or other suitable bases in THF, DMF orother appropriate solvents (N. V. Harris, C. Smith, K. Bowden, J. Med.Chem. 1990, 33, 434) to provide the intermediate 12 that is furtherreduced to the desired intermediates 5 by hydrogenation in the presenceof Pd/C or other reducing agents (Scheme 4).

Alternatively, the amide 12 can be prepared from the acid 1 or the ester10, by first reaction with nitro benzene 11 to provide the intermediates13 and 14, respectively. The ester 14 can be further hydrolyzed to theacid 13, and then the acid 13 is coupled to the amine 2 to provide theamide 12 (Scheme 5). Other esters can be used instead of the methylester including other alkyl esters, such as ethyl, butyl, tert-butyl toimprove the hydrolysis process.

As shown in Scheme6,3′-(3-amino-2-cyanophenoxy)-2′,2′-dimethyl-N-propylpropanamide 5 canbe prepared from another route by reacting the alcohol 3 with2,6-difluorobenzonitrile 15 (J. Thurmond et al, J. Med. Chem. 2008, 51,449) to provide the fluoro derivative 16 that can be further reactedwith ammonia to provide the desired intermediate 5.

Alternatively, the amide 16 can be prepared from the acid 1 or the ester10 by first reaction with the 2,6-difluorobenzonitrile 15 to provide theintermediates 17 and 18, respectively. The ester 18 can be furtherhydrolyzed to the acid 17, and then the acid 17 can then be coupled tothe amine 2 to provide the amide 16 (Scheme 7).

Another alternative to the synthesis of intermediate 5 is described inScheme 8. The acid 1 or ester 10 is reacted with2-amino-6-fluorobenzonitrile 4 to provide the acid 19 or the ester 20,respectively. The later can be alternatively prepared from theintermediates 13 and 14, respectively, by reduction of the nitro groupto the amino group using for example SnCl₂ or other appropriate knownreducing agents. The acid 19 or the ester 20 can then be converted usingthe usual procedures described above to the amide 5.

Commercially available 2-fluoro-6-nitrobenzonitrile 21 (N. Gueduira, R.Beugelmans, J. Org. Chem. 1992, 57, 5577-5585) can also be treated withthe alcohols 1, 10 or 3 to provide respectively the desiredintermediates 13, 14 and 12 (Scheme 9) that can be further converted to5 using procedures as described above.

Other approaches involve the alkylation of commercially availablephenols 22 or 23 with bromo derivatives 24, 25 or 26 to provideintermediates 13, 14, 12, 17, 18 or 16 that can be converted to 5 usingprocedures as described above. The bromo derivative 24 is commerciallyavailable. Compounds 25 and 26 can be prepared using conventionalmethods from 10, 24 or 3 as shown in Scheme 10 bellow. Bromo derivatives24, 25, and 26 can be replaced with chloro, iodo, mesylate, tosylateanalogs that are synthesized using known methods from the correspondingalcohols.

As shown in Scheme 11 below, Mitsunobu reaction can also be used tointroduce the side chain by reacting the phenols 22 or 23 with thealcohols 10 or 3 to produce the desired derivatives 12, 14, 16 or 18.

As shown in Scheme 12 below, 2-amino nitrile 5 can be converted in onestep to3′-(4-amino-2,2-dioxide-1H-benzo[c][1,2,6]thiadiazin-5-yloxy)-2′,2′-dimethyl-N-propylpropanamide,i.e., compound 9 by treatment with sulfonamide 27 in presence of DBU atelevated temperature or in a two steps process via its reaction withsulfamoyl chloride 7 to provide the intermediate 8 that is furthercyclized to 9 in the presence of NaOH (Marayanoff et al, J. Med. Chem.2006, 49, 3496 and references cited therein).

Alternatively (Scheme 13), 2-amino nitriles 19 and 20 can be convertedin one step by treatment with sulfonamide 27 in presence of DBU atelevated temperature to provide 1H-benzo[c][1,2,6]thiadiazin-5-yloxy)derivative 30 that can be further reacted with amine 2 to provide theamide 9. Amino nitriles 19 and 20 can also be converted to the cyclizedderivative 30 in two steps via the sulfonamides 28 and 29, respectively.

Alternative approaches to the preparation of useful intermediates in thesynthesis of compound 9 are described in Scheme 14, 15, and 16.

As shown in Scheme 14, amino nitriles 19, 20 and 5 can be converted tocorresponding amino amides derivatives by hydrolysis of the nitrilegroup. These intermediates can be further reacted with sulfamoylchloride to provide the sulfamides 34, 35 or 36 that can be cyclizedusing a variety of reagents such as EDCI (Chem. Pharm. Bull. 2004, 52,1422) or P₂O₅ to produce respectively 30, 37 or 9.

As shown in Scheme 15, amino amides 31, 32 and 33 can be reacted withsulfonyl chloride to provide the corresponding cyclized1H-benzo[c][1,2,6]thiadiazin-4-ols 38, 39 and 40. The hydroxyl can beconverted to a leaving group X (X=Cl, OMs, OTs, OTf) using conventionalmethods to provide intermediates 41, 42 or 43, that can be displacedwith ammonia (Bioorg. Med. Chem. Lett. 2005, 15, 3853) to provide thecorresponding 1H-benzo[c][1,2,6]thiadiazin-4-amines 30, 37 or 9.

Another approach is described in Scheme 16. Commercially available2,6-dinitrobenzoic acid 44 can be reacted with alcohol 3 to provide thenitro benzoic acid 45 that can be converted to the corresponding methylester (or other appropriate ester) to give 46. The nitro group can bereduced to the amino group using conventional method (for examplereduction in the presence of SnCl₂) and the ester 47 treated withammonia to provide the desired intermediate 33. Alternatively, thecarboxylic acid 45 can be reacted with sulfonyl chloride (to provide theacyl chloride) and then with ammonia to provide 48 that is furtherhydrogenated to give the desired intermediate 33.

In one embodiment of the present invention, the compound havingstructural Formula (I) is compound 53 below:

One approach to the synthesis of compound 53 (scheme 17) requires 3steps starting from commercially available 2,2-dimethylpropan-1-ol 50that is first reacted with 4 to provide the intermediate 51. Treatmentof 51 with sulfamoyl chloride 7 provide the sulfamoylamino derivative 52that is further cyclized to 53 in the presence of NaOH. The synthesiscan be done in a 2 steps process by reacting the intermediate 51 withsulfamide 27 in the presence of DBU or other suitable base at elevatedtemperature to provide directly the cyclized 53.

As shown in Scheme 18, the alcohol 50 can also be reacted withcommercially available 2,4-dinitrobenzonitrile 11 (N. V. Harris, C.Smith, K. Bowden, J. Med. Chem. 1990, 33, 434) or2-fluoro-6-nitrobenzonitrile 21 to provide the intermediate 54 that isfurther reduced to the desired intermediates 51 by hydrogenation in thepresence of Pd/C or other reducing agents.

As shown in Scheme 19,3′-(3-amino-2-cyanophenoxy)-2′,2′-dimethyl-propane 51 can be preparedfrom another route by reacting the alcohol 50 with2,6-difluorobenzonitrile 15 (J. Thurmond et al, J. Med. Chem. 2008, 51,449) to provide the fluoro derivative 55 that can be further reactedwith ammonia to provide the desired intermediate 51.

Another approach (as shown in Scheme 20) involves the alkylation ofcommercially available phenols 22 or 23 with commercially available1-bromo-2,2-dimethylpropane 56, 1-chloro-2,2-dimethylpropane 57 or1-iodo-2,2-dimethylpropane 58 to provide intermediates 54 and 55 thatcan be converted to 51 using procedures as described above. Bromo 56,Chloro 57 and Iodo 58 can be replaced with mesylate or tosylate analogsthat are synthesized using known methods from the correspondingalcohols. Mitsunobu reaction can also be used to introduce the sidechain by reacting the phenols 22 or 23 with the alcohol 50.

Alternates approaches to the preparation of useful intermediates in thesynthesis of compound 53 are described in Schemes 21, 22, and 23.

As shown in Scheme 21, amino nitrile 51 can be converted to itscorresponding amino amide derivative 59 by hydrolysis of the nitrilegroup. This intermediate 59 can be further reacted with sulfamoylchloride to provide the sulfamide 60 that can be cyclized using avariety of reagents such as EDCI or P₂O₅ to produce 53.

Alternatively, as shown in Scheme 22, amino amide 59 can be reacted withsulfonyl chloride to provide the corresponding cyclized1H-benzo[c][1,2,6]thiadiazin-4-ol 61. The hydroxyl can be converted to aleaving group X (X=Cl, OMs, OTs, OTO using conventional methods toprovide intermediate 62. The leaving group can be can be displaced withammonia to provide compound 53.

Another approach is described in Scheme 23. Commercially available2,6-dinitrobenzoic acid 44 can be reacted with alcohol 50 to provide thenitro benzoic acid 63 that can be converted to the corresponding methylester (or other appropriate ester) to give 64. The nitro group can bereduced to the amino group using conventional method (for example,reduction in the presence of SnCl₂) to provide 65 that is furtherreacted with ammonia to give the desired intermediate 59.

In one embodiment of the present invention, the sodium salt of compounds9 or 53 can be prepared by reacting 9 or 53 with NaOH, NaHCO₃, or Na₂CO₃(Scheme 24). Other suitable salts can also be made using appropriateprocedures, such as Potassium, Calcium and Magnesium salts. The saltsform of the compounds have better solubility in aqueous solution as wellas in polyglycol and other solvents that are used to make stocksolutions for food applications.

EXAMPLES

GC Conditions

Agilent GC with an Agilent HP-5 column, 30 m (L)×0.32 mm (ID)×0.25 μm(df)

Inlet Split; Split Ratio 100:1 Inlet Temperature 300° C. Inlet Pressure10.0 psi (constant pressure) Thermal Program Initial 50° C. (hold for0.70 min) Ramp to 300° C. (hold 5 min) at 30° C./min Detection FlameIonization Detector Temperature 320° C. Carrier Gas Helium Makeup GasHelium, 35 mL/min Air Flow 350 mL/min Hydrogen Flow 40 mL/min InjectionVolume 1 μL Run Time 14.03 min Diluent Compound 1 and Compound 2(methanol) Compound 3 (acetonitrile)

Approximate Retention Time, min Compound 1 3.690 Compound 2 6.0622-Amino-6-fluorobenzonitrile 6.099 Compound 3 10.874HPLC Conditions

Agilent HPLC with a Waters J′ sphere ODS-H80 C18 column, 4-μm particlesize, 4.6 mm×150 mm

Flow rate 1.0 mL/min Detection UV at 230 nm Column Temperature 25° C.Injection Volume 1 μL Run Time 30 min Mobile Phase A 0.1% formic acid inDI water Mobile Phase B 0.1% formic acid in acetonitrile Diluent1:0.5:0.5 formic acid:acetonitrile:DI water

Time (min) (%) Mobile Phase A (%) Mobile Phase B 0.0 95.0 5.0 20.0 5.095.0 25.0 5.0 95.0 27.0 95.0 5.0 30.0 95.0 5.0

Approximate Retention Time, min Compound 3 11.7 Compound 3a 10.0Compound 4 9.4

Example 1 Synthesis of Compound 3

To a 5-Gal pressure reactor was charged methyl3-hydroxy-2,2-dimethylpropanoate 10 (4.5 kg, 34.05 mol, 1 equiv.) andn-propylamine 2 (3.02 kg, 4.2 L, 51.07 mol, 1.5 equiv.) and the mixturestirred and heated to 120° C. The pressure of the reactor rose to 54psig and the temperature of the reactor was maintained by the use of aheating jacket and internal cooling coils that contained glycol. Thissetup did cause the internal pressure to fluctuate over a range of 30psig to 54 psig due to the cooling and heating of the vapor phase of thereactor. The reaction was monitored by GC and after 93 h the residualmethyl 3-hydroxy-2,2-dimethylpropanoate 1 was 1.95% (AUC) by GC relativeto compound 3. The contents of the reactor were then allowed to cool toambient temperature and the batch was transferred to a suitablecontainer and concentrated on a 20-L rotary evaporator using toluene toazeotropically remove residual methanol along with the low boilingn-propylamine. This gave compound 3 (5.65 kg, 86% (AUC by GC) as aconcentrate which had a high level of residual n-propylamine (˜3.44%)and was stored for combination with a 2^(nd) batch and observed tosolidify on standing.

A 2^(nd) batch was processed in a similar manner at the same scale togive compound 3 (5.267 kg, 86% (AUC) by GC) as a concentrate containing˜4% n-propylamine. A use test of compound 3 that contained ˜4.3%n-propylamine was conducted through to compound 5 and confirmed thatthis high level of residual n-propylamine did not affect the quality ofthe material produced.

Both of these batches were dissolved in anhydrous THF for subsequent usein the next step.

Example 2 Synthesis of Compound 5

To a dried 750-L reactor purged with nitrogen was charged NaH (60%dispersion in mineral oil, 3.6 kg, 90.0 mol, 1.7 equiv.) and low waterTHF (160 L) and the resulting slurry was cooled to 0-10° C. Compound 3(9.07 kg (theoretical based on wt % calculation of solutions), 57 mol,1.08 equiv. in anhydrous THF) was then further diluted with low waterTHF (71 L) and charged portionwise to the NaH/THF slurry maintaining thereaction temperature at 0-10° C. Once the addition was complete thereactor was warmed to 20-25° C. and held at this temperature for atleast 30 min. To this was slowly charged a solution of2-amino-6-fluorobenzonitrile (7.2 kg, 52.9 mol, 1 equiv.) 4 in low waterTHF (35.5 L) over a period of at least 30 min., maintaining the reactiontemperature at 20-30° C. Once the addition was complete the reactionmixture was heated to reflux and after 10 h the residual2-amino-6-fluorobenzonitrile was 1.7% (AUC) by GC relative to Compound5. The batch was concentrated to ˜⅓ volume (to ˜90 L) under partialvacuum distillation and diluted with MTBE (190 L) and washed with water(2×143 L). A sample of the organic layer was taken and tested forresidual fluoride and it was found to be at a concentration of 11.6 ppm.Since the fluoride number was higher than a concentration of 5 ppm, alevel at which had been deemed safe to operate at, a further water wash(143 L) was conducted along with a filtration through a 25 micron filterto remove black particles that were observed in the batch. Measurementof the residual fluoride was then repeated and determined to be at aconcentration of 2.8 ppm and the organic layer was concentrated to ˜⅓volume (to ˜90 L) under vacuum. The batch was diluted with EtOAc (190 L)and the process repeated, concentrating to ˜⅓ volume (to ˜90 L). TheEtOAc dilution (190 L) and concentration was repeated to ˜90 L and thebatch was cooled to 20-25° C. The resulting mixture was stirred at thistemperature until crystallization was observed at which point hexane(285 L) was added. The batch was further cooled to 15-25° C. and stirredat this temperature for at least 2 h before filtering and washing withhexane (2×35.5 L). The product was dried under vacuum at 50° C. for45.75 h to give Compound 5 as a white to off-white solid (10.15 kg, 70%yield) with a purity of 97% (AUC) by GC.

Example 3 Conversion of Compound 5 to Compound 9

To a dry 750-L reactor purged with nitrogen was charged CH₂Cl₂ (95 L),chlorosulfonyl isocyanate 6 (9.0 kg, 63.6 mol, 2.19 equiv.) andtriethylamine (161 g, 1.59 mol, 2.5 mol %) and the mixture was heated to36-42° C. In a container was mixed 99% formic acid (3.0 kg, 65.17 mol,1.02 equiv), CH₂Cl₂ (4.75 L) and triethylamine (161 g, 1.59 mol, 2.5 mol%). With a nitrogen sweep of the headspace being employed ˜10% aliquotsof the formic acid/triethylamine solution were added to thechlorosulfonyl isocyanate (CSI) mixture. Samples of the gas were takenperiodically after addition of the aliquot to confirm CO₂ gas formationand cessation and once CO₂ gas evolution had decreased the next aliquotwas added. Subsequent monitoring of the reaction of each aliquot couldnow easily be monitored visually by both foaming in the reactor and anoticeable decrease in the reaction temperature (˜3-4° C. per 10%aliquot). Once foaming had ceased and the batch had returned to itsoriginal temperature the next aliquot could be safely added. Uponaddition of the final aliquot and observed cessation of foaming andendotherming of the reaction, further gas samples were taken to confirmthat CO₂ generation had ceased during the 60-90 minute hold period.Although CO₂ was still detected at low levels, two consecutive readingsgave similar results and this was believed to be due to the nitrogensweeping through the headspace of the reactor which was not efficientlydisplacing all the CO₂ present in the reactor. This process transformedcompound 6 to compound 7.

The mixture containing compound 7 was then cooled to 0-10° C. anddiluted with MeCN (40 L) and stirred at this temperature for 30-45 min.to the secondary 750-L reactor was charged Compound 5 (8.0 kg, 29.05mol, 1 equiv.), CH₂Cl₂ (90 L) and dimethylacetamide (4 L) and wasstirred until a solution was formed before cooling to 0-10° C. To thiswas then added the solution of sulfamoyl chloride 7 in the primaryreactor over a period of 1-3 h maintaining the reactor temperature at0-10° C. After the addition was complete the batch was allowed to warmto 20-25° C. and stirred at this temperature overnight. The reaction wasmonitored by HPLC and after 10.33 h the reaction was deemed completewith 10% (AUC) compound 5 remaining by HPLC relative to compound 8. Themixture was slowly quenched onto a solution of NaHCO₃ (10.8 kg, 128.6mol) in water (110 L) over at least 1 h maintaining the reactiontemperature at 10-30° C. The layers were allowed to separate and theaqueous layer was back extracted with CH₂Cl₂ (2×40 L). The combinedorganics were then extracted with a solution of 50% NaOH (11.6 kg, 145mol, 5 equiv.) in water (137.6 kg) followed by 50% NaOH (1.55 kg, 19.38mol, 0.67 equiv.) in water (18.35 kg). The combined aqueous extractswere heated at 40-50° C. for ˜10 h followed by heating to 60-70° C. andholding at this temperature for ˜4 h until reaction completion wasobserved (<1% (AUC) Compound 8 vs Compound 9 by HPLC).

The reaction mixture was cooled to 20-25° C. and washed with MTBE (2×60L) before filtering through a 0.45 micron filter to remove any residualparticles. To the aqueous solution was then charged EtOH (190 proof, 96L) and the batch was cooled to 0-10° C. To this solution was slowlytransferred a solution of 37% HCl (17.86 kg) in water (30 L) over aperiod of at least 30 min. until the pH of the reaction mixture was˜4.5. At this point the batch had precipitated and was held at 0-10° C.for a minimum of 1 h before filtering and washing with DI water (2×25 L)followed by a 2:1 mixture of DI water/EtOH (25 L). The batch was driedunder vacuum at 40-50° C. for 40 h to give crude Compound 4 as a paleyellow solid (6.8 kg, 66% yield from Compound 5) with a purity of 93.2%(AUC) by HPLC.

Example 4 Purification of Compound 9

To the 750-L reactor was charged crude compound 9 (6.8 kg), EtOH (190proof, 68 L) and DI water (68 L). The resulting slurry was heated to75-85° C. and held at this temperature for 2 h before cooling to 15-25°C. overnight (˜16 h). The slurry was filtered and washed with a 2:1mixture of DI water/EtOH (28.4 L). The batch was dried under vacuum at40-50° C. for ˜15 h to give compound 9 as an off-white solid (6.4 kg,94% recovery) which contained ˜0.3% (AUC) compound 5 by HPLC.

The batch was reworked in an identical manor with the solvent amountsand wash volumes remaining unchanged. This gave compound 9 as a whitesolid (5.83 kg, 57% yield from compound 5) with a purity of 99.9% (AUC)and 0.03% (AUC) compound 5 by HPLC.

All publications and patent applications referenced herein areincorporated by reference to the same extent as if each individualpublication or patent application was specifically and individuallyindicated to be incorporated by reference.

While the present invention has been particularly shown and describedwith respect to preferred embodiments thereof, it will be understood bythose skilled in the art that the foregoing and other changes in formsand details may be made without departing from the spirit and scope ofthe invention. It is therefore intended that the present invention notbe limited to the exact forms and details described and illustrated butfall within the scope of the appended claims.

We claim:
 1. A process of preparing a compound having structural Formula(I):

comprising reacting a compound having structural Formula (II)

with a base or an activating reagent, wherein R¹ is —CN or —C(O)NH₂; andX is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl.
 2. The process of claim 1, comprising reacting a compoundhaving structural Formula (IIa)

with an activating reagent to provide the compound of Formula (I). 3.The process of claim 1, comprising reacting a compound having structuralFormula (IIb)

with a base to provide the compound of Formula (I).
 4. A process ofpreparing a compound having structural Formula (I):

comprising reacting a compound having structural Formula (III)

with NH₂S(O)₂NH₂ or Cl—S(O)₂—NH₂ optionally in the presence of a base,to provide directly the compound having structural Formula (I), oralternatively to provide the compound having structural formula (II) ofclaim 1 which is further reacted with an inorganic base or an activatingreagent to provide the compound having structural Formula (I), whereinR¹ is —CN or —C(O)NH₂; and X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl.
 5. A process of preparing acompound having structural Formula (I):

comprising reacting a compound having structural Formula (VII)

with NH₃ or NH₃.H₂O; wherein X is alkyl, substituted alkyl, alkenyl,substituted alkenyl, heteroalkyl, substituted heteroalkyl,heteroalkenyl, or substituted heteroalkenyl; and R⁷ is a leaving groupselected from the group consisting of halo, —OMs, —OTs, and —OTf.
 6. Acompound having structural Formula (VII):

wherein X is alkyl, substituted alkyl, alkenyl, substituted alkenyl,heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substitutedheteroalkenyl; and R⁷ is a leaving group selected from the groupconsisting of halo, —OMs, —OTs, and —OTf.
 7. A process of preparing acompound having structural Formula (Ia):

comprising reacting a compound having structural Formula (VIII)

with R⁸—NH₂, in the presence of an activating reagent; wherein Y isC1-C12 alkylene or C1-C12 alkenylene; R⁸ is C1-C12 alkyl; and R⁹ ishydrogen or C1-C12 alkyl.
 8. The process of any of the claim 1, 4, and5, wherein the compound having structural Formula (I) is


9. A process of preparing a compound having structural Formula (Ib):

comprising reacting a compound having structural Formula (I)

with an alkali metal- or alkaline earth metal-based inorganic base,wherein M is a cation of alkali metal or alkaline earth metal; X isalkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl,substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl; nis 1, when M is a cation of alkali metal; and n is 2, when M is a cationof alkaline earth metal.
 10. The process of claim 9, wherein X is C1-C12alkyl, C1-C12 heteroalkyl, C1-C12 alkenyl, C1-C12 heteroalkenyl,—Y—C(O)—OR², or —Y—C(O)—NH—R²; Y is C1-C12 alkylene or C1-C12alkenylene; and each R² is independently hydrogen or C1-C12 alkyl. 11.The process of claim 9, wherein the compound having structural Formula(Ib) is


12. A process of preparing a compound having structural Formula (Ia):

comprising reacting a compound having structural Formula (IIc1)

with a hydroxide or alkoxide base in an aqueous solution at atemperature ranging from about 25 to about 95° C., wherein Y is C1-C12alkylene or C1-C12 alkenylene; and R⁸ is C1-C12 alkyl.
 13. The processof claim 11, wherein the compound having structural formula (Ia) is